Ligand binding to stromelysin and the associated conformational shifts were monitored through the fluorescence of the three intrinsic tryptophan residues. Fluorescence lifetime and dynamic polarization data were taken across the protein's emission band in the presence and absence of ligand. The data were analyzed with Globals Unlimited for multi-exponential fluorescence lifetime decays and, from the dynamic polarization data, for global and local rotational modes. The emission dependence of these time-resolved fluorescence parameters will be examined to determine if the spectral differences among the three intrinsic tryptophans is sufficient to place specific conformational shifts to particular tryptophan residues. It is hoped that the sophisticated time-resolved studies will help separate the effects of the tryptophans where steady-state measurements have been unsuccessful.